--- a/flys-artifacts/ChangeLog	Thu Apr 28 11:20:11 2011 +0000
+++ b/flys-artifacts/ChangeLog	Thu Apr 28 11:22:45 2011 +0000
@@ -1,3 +1,9 @@
+2011-04-28  Ingo Weinzierl <ingo@intevation.de>
+
+	* src/main/java/de/intevation/flys/artifacts/transitions/ValueCompareTransition.java:
+	  New. This transition is valid if the a data object of the current
+	  artifact equals/notequals a configured value in the transition model.
+
 2011-04-28  Ingo Weinzierl <ingo@intevation.de>
 
 	* src/main/java/de/intevation/flys/artifacts/WINFOArtifact.java,

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/transitions/ValueCompareTransition.java	Thu Apr 28 11:22:45 2011 +0000
@@ -0,0 +1,118 @@
+package de.intevation.flys.artifacts.transitions;
+
+import javax.xml.xpath.XPathConstants;
+
+import org.apache.log4j.Logger;
+
+import org.w3c.dom.Node;
+
+import de.intevation.artifacts.Artifact;
+
+import de.intevation.artifactdatabase.data.StateData;
+import de.intevation.artifactdatabase.state.State;
+
+import de.intevation.artifacts.common.utils.XMLUtils;
+
+import de.intevation.flys.artifacts.FLYSArtifact;
+
+
+/**
+ * This transition compares data objects with a <i>equal</i> or <i>notequal</i>
+ * operator.
+ *
+ * @author <a href="mailto:ingo.weinzierl@intevation.de">Ingo Weinzierl</a>
+ */
+public class ValueCompareTransition extends DefaultTransition {
+
+    /** The logger that is used in this transition.*/
+    private static Logger log = Logger.getLogger(ValueCompareTransition.class);
+
+
+    /** XPath that points to the condition's operator.*/
+    public static final String XPATH_OPERATOR = "condition/@operator";
+
+    /** XPath that points to the condition's value.*/
+    public static final String XPATH_VALUE    = "condition/@value";
+
+    /** XPath that points  to the condition's dataname.*/
+    public static final String XPATH_DATANAME = "condition/@data";
+
+    /** The value of the 'equal' operator.*/
+    public static final String OPERATOR_EQUAL = "equal";
+
+    /** The value of the 'not equal' operator.*/
+    public static final String OPERATOR_NOTEQUAL = "notequal";
+
+
+    /** The operator.*/
+    protected String operator;
+
+    /** The value used for comparison.*/
+    protected String value;
+
+    /** The name of the data used for the comparison.*/
+    protected String dataname;
+
+
+
+    public ValueCompareTransition() {
+    }
+
+
+    public ValueCompareTransition(String from, String to) {
+        super(from, to);
+    }
+
+
+    @Override
+    public void init(Node config) {
+        log.debug("ValueCompareTransition.init");
+
+        String tmp = (String) XMLUtils.xpath(
+            config,
+            XPATH_OPERATOR,
+            XPathConstants.STRING);
+        operator = tmp.trim().toLowerCase();
+
+        value = (String) XMLUtils.xpath(
+            config,
+            XPATH_VALUE,
+            XPathConstants.STRING);
+
+        dataname = (String) XMLUtils.xpath(
+            config,
+            XPATH_DATANAME,
+            XPathConstants.STRING);
+    }
+
+
+    @Override
+    public boolean isValid(Artifact artifact, State a, State b) {
+        log.debug("ValueCompareTransition.isValid");
+
+        FLYSArtifact flysArtifact = (FLYSArtifact) artifact;
+
+        StateData dataObj = flysArtifact.getData(dataname);
+        String    dataVal = dataObj != null ? (String) dataObj.getValue() : "";
+
+        if (log.isDebugEnabled()) {
+            log.debug("Compare settings:");
+            log.debug("-- dataname: " + dataname);
+            log.debug("-- operator: " + operator);
+            log.debug("-- compare value: " + value);
+            log.debug("-- state value: " + dataVal);
+        }
+
+        if (operator.equals(OPERATOR_EQUAL)) {
+            return value.equals(dataVal);
+        }
+        else if (operator.equals(OPERATOR_NOTEQUAL)) {
+            return !(value.equals(dataVal));
+        }
+
+        log.error("Wrong operator set! No comparison takes place.");
+
+        return false;
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :